An operating machine such as a power shovel includes an operating portion such as a bucket. Various drilling tools are attached to the operating portion. For example, multiple adaptors are, at predetermined intervals, fixed to a tip end portion of the bucket of the power shovel for drilling. Moreover, teeth as the drilling tools are each attached to the adaptors. The teeth are abraded or damaged in a drilling process, and therefore, are replaced as necessary.
Patent Literature 1 discloses such an attachment pin assembly for attaching the tooth to the adaptor of the bucket.
A pair of first through-holes is formed at the tooth described in Patent Literature 1, and on the other hand, a second through-hole is formed at the adaptor. In an attachment state in which the adaptor is inserted into the tooth in contact with the tooth, the first through-holes and the second through-hole are arranged to penetrate the tooth and the adaptor. Moreover, in the tooth attachment state, the centers of the first through-holes and the second through-hole are coincident with each other, and are in a concentric state.
The attachment pin assembly of Patent Literature 1 includes a circular columnar pin body inserted into the first through-hole and the second through-hole, a cylindrical bush arranged at an end portion of the pin body in the first through-hole, and a bolt and a washer provided at each end of the pin body to prevent detachment of the bush from such an end of the pin body. A head of the bolt laterally protrudes from the end portion of the pin body. The tooth is thickly formed in a longitudinal direction of the pin body to surround the head of the bolt. Thus, the head of the bolt receives less impact from a rock, a rubble, etc. upon use of the tooth.